Played smoothly (6)
I believe the answer is:
legato
'played smoothly' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for legato that I've seen before include "Smoothly flowing in style" , "(Music) without breaks between notes" , "Smoothly, musically speaking" , "Smoothly (mus.)" , "Musically smooth" .)